1. Technical Field
The present disclosure relates generally to instrumentation for inserting an implant into a body receiving bed. More particularly, the present disclosure relates to instrumentation for guiding and positioning a dowel into a receiving bed formed in an intervertebral space.
2. Background to Related Art
Distractors and guide sleeves for positioning an implant into a receiving bed in the intervertebral space are well known. These distractors include forceps type distractorS as well as wedge type distractors which are pushed into the intervertebral space and distract upon insertion. The guide sleeve typically includes a cylindrical sleeve which is mounted to the adjacent vertebrae such that the instruments and implant can be positioned in the intervertebral space through the cylindrical sleeve. At least with respect to wedge type distractors, distraction of the vertebrae occurs unevenly with the front face of the vertebrae being distracted first. This is not desirable.
Accordingly, a need exists for an improved distractor/guide sleeve assembly which includes a simple integral assembly and provides for uniform distraction of adjacent vertebrae. A need also exists for an insertion tool useable with the distractor/guide sleeve assembly for inserting an implant into the intervertebral space.
In accordance with the present disclosure, a distractor/guide sleeve assembly is provided which includes a body having a cylindrical throughbore and a distractor assembly mounted thereon. The distractor assembly includes a rotatable dial, a pair of distractor rods, and two pairs of jaws. A plate is secured to the distal end of each distractor rod. Each plate includes a plurality of cam members which are slidably positioned in cam slots formed in the jaws of each of the pairs of jaws. The dial is operably connected to the distractor rods such that rotation of the dial effects axial movement of the distractor rods. Axial movement of the distractor rods cause corresponding movement of each of the plates to move the cam members within the cam slots formed in each of the jaws. Movement of the cam members within the cam slots effects movement of each of the pairs of jaws between approximated and distracted positions.
An insertion tool is also provided which includes a handle and distal engaging structure for releasably engaging an implant. The engaging structure includes a pair of prongs or protrusions having a slip resistant outer surface. The prongs are configured to be releasably received within correspondingly shaped bores formed in an implant.